For devices such as wireless gateways/wireless routers which have the function of 2G/3G wireless access, they usually have at least one Wireless Wide Area Network (WWAN) interface and one Local Area Network (LAN) interface, the WWAN interface is connected to the Internet through the 2G/3G wireless technology, and the LAN interface is connected to multiple user terminals by means of a cable or WiFi, to provide 2G/3G wireless Internet access function.
For the IPv4, the wireless devices allocate the private network address specified by RFC1918 to the LAN interface and the user terminal connected thereto and allocate the legal IPv4 address allocated by the network to the WAN interface through the DHCPv4 protocol, the wireless devices implement routing of the IPv4 data message between the LAN interface and the WAN interface and translation between the private IPv4 address and the legal IPv4 address through route and NAT technology, thus all users at the LAN side share one legal IPv4 address to communicate with the Internet network.
For the IPv6, in the 3GPP TS 23.060 technical specification, two IPv6 address dynamic allocation modes are defined for the wireless device, i.e., a stateful address auto-configuration and a stateless address auto-configuration, and one global unicast address prefix is allocated to the wireless device with these two address auto-configuration technologies, and the prefix has a length of 64 bits. Since the maximum of the length of the global unicast address prefix is 64, the wireless devices can not further divide the prefix into two or more prefixes, and in addition, the IPv6 has abandoned the Network Address Translation (NAT) technology, which means that the wireless devices can only allocate the prefix to WAN and LAN interfaces for sharing, and in that case, the WAN and LAN interfaces of the wireless device belong to the same segment, and operate in a bridge mode.
For the IPv4, the WAN and LAN interfaces of the wireless device belong to different segments, and the wireless device operates in a route mode; and for the IPv6, the WAN and LAN interfaces of the wireless device belong to the same segment, and the wireless device operates in a bridge mode. For the IPv4 or IPv6 single stack, the wireless devices can operate normally, but in the IPv4/IPv6 double stack mode, the IPv4 and IPv6 protocol stacks can not operate normally, because the wireless devices can not operate in the route mode and the bridge mode at the same time. In addition, when the wireless devices operate in the bridge mode, a broadcast storm will be generated easily, consuming precious radio wireless resources.
In conclusion, under the condition of the prior art, the wireless device using a single 64-bit-long IPv6 address prefix can not operate in the route mode, i.e., configuring the LAN and WAN interfaces in different segments.